Table 4. Plasma and CSF levels of Aβ.
| Control-N n = 200 | Control-P n = 74 | SCD-P n = 60 | MCI-P n = 121 | AD-P n = 53 | |
|---|---|---|---|---|---|
| Plasma Aβ42 pg/ml | 20.1 (5.4) | 18.3 (4.2))a | 17.4 (5.6)a | 17.6 (4.9)b | 12.9 (7.1)b,c,d,e |
| Plasma Aβ40 pg/ml | 274.6 (70.9) | 282.3 (51.3) | 271.9 (67.9) | 284.3 (72.8) | 238.7 (105.5)b,e,f,g |
| Plasma Aβ42/Aβ40 | 0.076 (0.026) | 0.065 (0.010)b | 0.065 (0.018)a | 0.063 (0.013)b | 0.057 (0.023)b |
| CSF Aβ42 pg/ml | 604.7 (172.0) | 416.9 (189.1)b | 369.1 (127.7)b | 354.5 (152.4)b | 291.3 (105.4)b,c,h,i |
| CSF Aβ40 pg/ml | 4373.1 (1378.8) | 5540.9 (1997.5)b | 5395.2 (1949.4)b | 5129.0 (1937.2)b | 4548.3 (1712.6)f,j |
| CSF Aβ42/Aβ40 | 0.141 (0.023) | 0.075 (0.016)b | 0.070 (0.015)b | 0.071 (0.017)b | 0.067 (0.018)b |
Data are shown as mean (SD).
AD, Alzheimer’s disease; CSF, cerebrospinal fluid; MCI, mild cognitive impairment; SCD, subjective cognitive decline; N, normal CSF signature (CSF Aβ42/Aβ40 ratio > 0.1); P, pathologic CSF signature (CSF Aβ42/Aβ40 ratio ≤0.1).
Plasma and CSF Aβ were measured using Simoa and Euroimmun immunoassays, respectively. Plasma and CSF biomarkers were analyzed with univariate general linear models controlling for age and gender; statistical significance was set to p < 0.005 to account for Bonferroni correction; acompared with control-N, p < 0.001; bcompared with control-N, p < 0.0001; ccompared with control-P, p < 0.0001; dcompared with SCD-P, p < 0.0001; ecompared with MCI-P, p < 0.0001; fcompared with control-P, p < 0.001; gcompared with SCD-P, p < 0.001; hcompared with SCD-P, p = 0.003; icompared with MCI-P, p = 0.005; jcompared with SCD-P, p = 0.002.